Oil supply means for a machine

Abstract

The invention comprises a subsystem or assembly which lends itself to retro-fitting to a machine to controllingly supply oil to the machine. In the embodiment shown by way of example, the invention supplies injection oil and lubricating oil to an oil-injected and oil-lubricated gas compressor, and includes a pressure-responsive metering device for regulating the relative quantities of injection and lubricating oil supplied pursuant to the operating condition of the compressor. Particularly the invention comprises the use of a small, inexpensive oil pump, to supply substantially only lubrication for the compressor on start-up, and by-passes the pump, when substantially "on line" (i.e., with the compressor discharge pressure elevated), and then supplies less of the oil for lubrication purposes and more for injection (for compressor sealing and cooling).

I claim: 
     
       1. Oil supply means, for a machine such as a gas compressor, gas expander, pump, and the like, comprising: a reservoir of oil;   means defining a source of gas at excursive pressures;   means communicating said reservoir and said source for pressuring said reservoir with said excursive pressures of said source;   oil conducting means communicating with said reservoir for conducting oil therefrom to a machine;   oil shunting means communicating with said oil conducting means for shuntingly diverting oil from said oil conducting means to diminish oil flow via oil conducting means; and   means interposed in said oil conducting means for meteringly controlling oil flow therethrough to cause varying quantities of oil to be shuntingly diverted therefrom to said oil shunting means; wherein   said controlling means comprises means responsive to attenuating pressures of said reservoir for diminishing oil flow through said oil conducting means, and causing increased oil flow through said shunting means, and responsive to elevating pressures in said reservoir to increase oil flow through said oil conducting means and to diminish oil flow through said shunting means.   
     
     
       2. Oil supply means, according to claim 1, wherein: said gas source defining means comprises a gas compressor;   said gas compressor having a gas output port;   said oil reservoir comprises a gas/oil separator; and   said oil conducting means comprises a conduit communicating said output port with said oil separator.   
     
     
       3. Oil supply means, according to claim 2, wherein: said controlling means comprises a housing having a chamber formed therein having first and second, external, spaced apart ports formed therein which open onto said chamber and metering means movably disposed in said chamber for meteringly controlling fluid flow communication, through said chamber, between said ports;   said housing further having a cylinder formed therein;   said metering means comprises a piston, slidably disposed in said cylinder for movement therewithin in first and second directions;   means within said cylinder engaging a first surface of said piston for biasing said piston in said first direction; and   means for admitting oil from said shunting means to a second, opposite surface of said piston to urge said piston in said second direction.   
     
     
       4. Oil supply means, according to claim 3, further including: means communicating said gas source with said first surface of said piston.   
     
     
       5. Oil supply means, according to claim 1, further including: a check valve interposed in said oil conducting means, intermediate said reservoir and said oil-diverting means, for preventing oil flow via said oil conducting means to said reservoir.   
     
     
       6. Oil supply means, according to claim 5, further including: a pump through-connected with said oil conducting means, in parallel with said check valve, for impelling oil flow via said oil conducting means.   
     
     
       7. Oil supply means, according to claim 6, wherein: said check valve comprises means normally closed to a conduit of oil therethrough, and responsive to a given range of oil pressures for conducting oil therethrough in by-pass of said pump.   
     
     
       8. Oil supply means, for use in combination with an oil/compressed gas separator, and an oil-injected and oil-lubricated gas compressor which has a discharge port which discharges compressed gas, at excursive pressures, into said separator, comprising: a first conduit, for communicating one end thereof with the separator for conducting oil therefrom, and for communicating with the compressor, via the other end thereof, to supply injection oil to the compressor;   a second conduit having one end thereof in communication with an intermediate portion of said first conduit, for shuntingly diverting oil from said first conduit, and for communicating with the compressor, via the other end thereof, to supply lubricating oil to the compressor;   metering means, interposed in said first conduit, intermediate said second conduit and said other end of said first conduit, operative for meteringly controlling oil flow through said first conduit and causing varying quantities of oil to be shuntingly diverted therefrom to said second conduit; and   pressure-responsive operating means, coupled to said metering means, for operating said metering means; wherein   said operating means comprises a translatable piston having a pair of opposed, fluid-impingement surfaces; and further including   means communicating said second conduit with a first of said surfaces to oil-pressure said surface to urge said piston in a first translating direction; and   means for communicating the second of said surfaces with the discharge port of the compressor to gas-pressure said second surface to urge said piston in a second translating direction.   
     
     
       9. Oil supply means, according to claim 8, further including: means normally urging said piston in said second direction.   
     
     
       10. Oil supply means, according to claim 8, further including: biasing means, engaged with said second surface of said piston, normally urging said piston in said second direction.   
     
     
       11. Oil supply means, according to claim 10, further including: an oil pump, interposed in said first conduit, intermediate said second conduit and said one end of said first conduit, for impelling oil through said first conduit.   
     
     
       12. Oil supply means, according to claim 11, further including: means interposed in said first conduit, in parallel with said oil pump, normally closed to a conduit of oil therethrough, and responsive to a given range of oil pressures for conducting oil therethrough to by-pass said pump.   
     
     
       13. Oil supply means, according to claim 12, wherein: said normally-closed, first-conduit interposed means comprises a check valve for preventing oil flow through said first conduit toward said one end of said conduit.